This lengthy, highly ambitious, phantasmagoric treatment of the ineffable Holocaust is far less accessible than Grossman's critically acclaimed The Yellow Wind , nonfiction reportage that elucidated the West Bank imbroglio. What begins as a wrenching portrait of Momik, an emotionally scarred nine-year-old Israeli child of Holocaust survivors, and his warped fantasy world, soon metamorphoses into fiction penned by the adult Momik. Now a self-conscious, tortured writer, Momik the man believes he is the vessel for new prose by both Bruno Schulz, the legendary Polish-Jewish author murdered by the Nazis, and Momik's great-uncle, Anshel Wasserman, whose popular children's adventures are updated and distorted as Momik imagines him spinning tales for a Nazi commandant of a concentration camp. Although stylistically daring, the bulk of Grossman's novel never re-creates the pathos that introduced Momik the child. As Wasserman's story unfolds, ``without any appreciable logic or trace of plot, without concern for the sacred unity of time and place,'' its appeal will elude many readers. (Apr.)